in Cartesian philosophy, a way of searching for certainty by systematically though tentatively doubting everything. First, all statements are classified according to type and source of knowledge-e.g., knowledge from tradition, empirical knowledge, and mathematical knowledge. Then, examples from each class are examined. If a way can be found to doubt the truth of any statement, then all other statements of that type are also set aside as dubitable. The doubt is methodic because it assures systematic completeness, but also because no claim is made that all-or even that any-statements in a dubitable class are really false or that one must or can distrust them in an ordinary sense. The method is to set aside as conceivably false all statements and types of knowledge that are not indubitably true. The hope is that, by eliminating all statements and types of knowledge the truth of which can be doubted in any way, one will find some indubitable certainties.
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